US7010779B2 - Parser, code generator, and data calculation and transformation engine for spreadsheet calculations - Google Patents

Abstract

A system including spreadsheet sheets, makes calculations and data transformations, which is available through a programming interface, and conforms to the grammar and syntax of a target software development language is presented. The system includes an Object Model with Data Structures representing entities involved in spreadsheets. The system includes a Parser and Code Generator that extracts data from a body of spreadsheet data, instantiates instances of Data Structures of the Object Model to represent the spreadsheet data, parses the data and formulas contained in the cells of the spreadsheets, iterates through the instantiated instances of the Data Structures, and generates source code that performs the calculations and data transformations embodied in the spreadsheet data. The system includes a Calculation Engine with software base classes that implement the common structural and data access features of spreadsheet data, and further implement the operations of common spreadsheet functions and operators.

Description

CROSS-REFERENCE

This application claims the benefit of appln. 60/312,981 filed Aug. 16, 2001.

FIELD OF THE INVENTION

The present invention pertains in general to software based calculation and data transformation engines, and more particularly, to conversion of the calculation and data transformation features of spreadsheet data into source code of a target software development language for independent run-time execution.

BACKGROUND OF THE INVENTION

Spreadsheet applications for computers, such as IBM's Lotus 123® and Microsoft® Excel, have become very popular analysis and communication tools. Spreadsheets are typically used to perform numerical analyses and ‘what if’ analyses, to simulate complex systems, and to communicate ideas. Many users are familiar with the spreadsheet metaphor. With little or no training, users can create complex, interrelated calculations and data transformations in spreadsheet applications.

The rapid growth and adoption of the Internet has spawned an explosion in web-based distribution of application functionality and server-based applications. Many such distributed and server-based applications have underlying logic that comprises complex calculations and data transformations. Development of such functionality in software language source code can be effort intensive, tedious, and error-prone. Furthermore, creating such functionality requires highly skilled software developers.

Being able to embed the calculations and data transformations of a spreadsheet directly into stand-alone applications, distributed applications, and server-based applications can be very powerful. Some spreadsheet applications have application programming interfaces (APIs) that allow them to provide calculation and data transformation as a service to other applications. But distributing and using spreadsheets in this way requires that users have the same or a compatible spreadsheet application as the one in which the spreadsheet was created.

Using spreadsheet applications as calculation engines in server-based applications also has limitations. Background art spreadsheet applications are meant for single users and cannot scale to support high-volume server-side processing. Also, the User Interface and display features of spreadsheet applications carry significant overhead.

There are background art spreadsheet components available that can read and write spreadsheet data created by popular spreadsheet applications and perform calculations at runtime. These components do facilitate the integration of spreadsheet functionality into other distributed applications or server-based applications. But these components operate internally in the same way spreadsheet applications do: they interpret Cell formulas at runtime. Runtime interpretation of Cell formulas is generally considered to be a desirable feature because it allows Cell formulas to be changed at runtime. But in many application scenarios, calculations and data transformations need to remain unchanged at runtime. So when a spreadsheet component is used as a calculation engine in such an application, then the runtime Cell formula interpretation feature adds memory and processing overhead without adding any value. Background art spreadsheet components are typically larger than 1 Megabyte in size.

When using background art spreadsheet components in server-based applications, the overhead associated with the User Interface and runtime cell formula interpretation features can negatively impact server performance, both from processing speed and memory usage standpoints. When using background art spreadsheet components in distributed applications, the overhead can also significantly degrade download performance.

Some spreadsheet applications and spreadsheet components use mechanisms to represent simple cell formulas as machine code during idle time processing. While this can reduce the negative performance impact related to run-time cell formula interpretation, it maintains the memory overhead and it can limit the spreadsheet application or spreadsheet component to running on only a single platform.

It would be desirable to provide a facility for automatically generating source code from spreadsheet data such that the generated source code embodies the calculations and data transformations embodied in the spreadsheet data. The generated source code may then be integrated into a wide variety of different types of applications or other utilization mechanisms. The calculations and data transformation may allow features to be accessed by users who do not have a spreadsheet application or spreadsheet component, or who have a spreadsheet application or spreadsheet component that is incompatible with the original spreadsheet application. The calculations and data transformation may protect features from being modified accidentally or deliberately. Thus, spreadsheet applications may be used as design tools for creating and testing complex, interrelated calculation functionality for use in a wide variety of applications. The calculations and data transformation allows features to be embedded into high-volume server architectures, such as mainframe computers or super computers, that are not fully supported by background art spreadsheet applications or components. Moreover, the calculations and data transformation may allow features to be embedded into disparate or distributed computing environments, such as web-browsers, embedded systems, gaming consoles, cell phones, and personal digital assistants (PDAs), that are not fully supported by background art spreadsheet applications or components.

One of the most labor-intensive aspects of software development is testing to verify that the software meets specifications. In many software development efforts, major parts of the system must be built before any of the parts can be tested. This makes it difficult to localize the origin of errors. But when using a spreadsheet to develop the core logic of a system it is easy to create multiple sets of test data and switch between the sets to test the spreadsheet. Therefore, it would be desirable to provide a core functionality that can be verified locally, before deployment and without writing any code.

SUMMARY OF THE INVENTION

Developing complex logic in a spreadsheet is much more efficient than hand-coding in a software language. The visual nature of spreadsheets and usability features like drag-copy have been critical to their widespread adoption. When these productivity enhancers are applied to programming, the effects are no less dramatic. Developers can create calculations and data transformation routines in a spreadsheet in a fraction of the time that it takes to do the same in code. Sophisticated systems may incorporate with built-in functions. Beginning developers can be effective at coding logic that might otherwise require a very skilled resource.

Briefly summarized, the present invention relates to source code generator programming interfaces defined to facilitate the analysis of a body of spreadsheet data and the generation of software source code representative of the body of spreadsheet data. The generated software source code embodies structural aspects of the body of spreadsheet data. The calculations and data transformations are performed thorough a plurality of spreadsheet sheets. This makes the calculations and data transformations available through a programming interface. Further, the grammar and syntax is conformed to a target software development language.

A preferred embodiment of the Parser and Code Generator integrated directly into a spreadsheet application. The preferred embodiment optionally generates source code conforming to the syntax of multiple target software development languages, including Java® by Sun Microsystems, C, C++, and others.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagram of representative computer system hardware in accordance with a preferred embodiment;

FIG. 2 shows a screen shot of a representative spreadsheet application in accordance with a preferred embodiment;

FIG. 3 shows a screen shot of a control interface displaying user-configurable properties integrated directly into a spreadsheet application, in this case Microsoft® Excel in accordance with the invention;

FIG. 4 a is a sample generated source code representative of global aspects of a body of spreadsheet data;

FIG. 4 b is a screen shot of generated source code representative of aspects of a single spreadsheet sheet;

FIG. 4 c is a sample representative spreadsheet cell formula and representative generated code;

FIG. 5 is a sample representative spreadsheet-like application interfacing with the Calculation Engine for values from an underlying compiled module representative of a body of spreadsheet data to provide calculation and data transformation features of the represented spreadsheet;

FIG. 6 is a sample representative non-spreadsheet-like applet interfacing with the Calculation Engine in a web browser environment for values from an underlying compiled module representative of a body of spreadsheet data to provide calculation and data transformation features of the represented spreadsheet;

FIG. 7 is a Flow Chart depicting overview of Code Generation Operation;

FIG. 8 is a Flow Chart depicting GetColorSchemes sub-operation of Code Generation Operation;

FIG. 9 is a Flow Chart depicting ConnectSheets sub-operation of Code Generation Operation;

FIG. 10 is a Flow Chart depicting ConnectNames sub-operation of Code Generation Operation;

FIGS. 11 a–11 e are Flow Charts depicting ParseCellFormulas sub-operation of Code Generation Operation;

FIG. 12 is a Flow Chart depicting KDBook.GetCode sub-operation of Code Generation Operation;

FIG. 13 is a Flow Chart depicting KDSheet.GetCode sub-operation of Code Generation Operation;

FIG. 14 is a Flow Chart depicting GetFuncLibCode sub-operation of Code Generation Operation;

FIG. 15 is a Flow Chart depicting DeployCode sub-operation of Code Generation Operation;

FIG. 16 illustrates Use Case diagram depicting the basic high-level use cases for the Calculation Engine;

FIG. 17 is a UML Class diagram depicting basic classes used within the Calculation Engine. Some details, such as the public application programming interface (API) methods, are set forth with reference to the data structures used in the calculation engine;

FIG. 18: In accordance with a preferred embodiment, a UML Sequence Diagram depicting basic operations and classes involved with loading an instance of the Calculation Engine;

FIG. 19 is a UML Sequence Diagram depicting basic operations and classes involved with getting a value within the Calculation Engine; and

FIG. 20 is a UML Sequence Diagram depicting basic operations and classes involved with setting a value within the Calculation Engine.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the figures and particularly FIG. 1, a block diagram of the representative computer hardware is shown illustrating a computer system implementing a source code generator with methods employing a process and computer-readable medium containing instructions for controlling the computer system, which comprises a processor or CPU 100 receiving input from a keyed input device 102 or pointing device 104. A display device 106 and printing device 108 are provided for output and volatile storage 110 and non-volatile storage 112 may include computer-readable media and random access memory and the like. As described further below, a spreadsheet application 116 is employed with a plurality of sheets from which a data structure including calculation files are used for corresponding spreadsheet data. A data acquisition interface is used for receiving the spreadsheet data, which is transferable to the calculation files. A parser and source code generator 118 is used for extracting information from the data structure. An information processor facilitated the use of CPU 100 for performing a data transformation of extracted information stored in said data structure through said programming interface to conform to the grammar and syntax of a target software development language. A calculation engine 120 is provided, which has the following benefits:

• • (a) allowing spreadsheet applications to be relied upon to verify well-formedness of cell formulas;
  • (b) reducing distribution size by eliminating the overhead of a spreadsheet application or spreadsheet component;
  • (c) reducing distribution size by eliminating the overhead of User Interface features and run-time cell formula interpretation features;
  • (d) allowing the generated code to be executed on any platform which supports a target software development language;
  • (e) improving the performance of the calculations and data transformation features because they are embodied in compiled code rather than being interpreted at runtime;
  • (f) improving the performance of the calculations and data transformation features because optimizing compilers can optimize for a target platform;

Within the field of object orientation, the concepts of encapsulation, polymorphism, and inheritance are well known. A Class is an embodiment of characteristics and behaviors. An instance of a Class is an object that exhibits the characteristics and behaviors of the Class. There are many well-known and widely available references describing object-oriented principles in great detail.

Within the field of computer applications, spreadsheet concepts are well known. In a typical background art spreadsheet application, a body of spreadsheet data comprises a singleton Workbook comprising a plurality of Worksheets. Worksheets comprise a plurality of Cells that can contain literal data values or formulas that are dependent on other Cells. Individual Cells as well as Ranges of Cells can be Named and can be referred to and accessed by Name. There are many well-known and widely available references describing spreadsheet principles and specific spreadsheet applications and components in great detail.

The disclosed invention comprises several data structures that represent the various entities of a spreadsheet. In a preferred embodiment, the data structures are object-oriented software classes that embody characteristics and behaviors of said spreadsheet entities. The Data Structures may be representative of spreadsheet entities, which may be instantiated as Extensible Markup Language (“XML”) data representative of spreadsheet entities. Some of these Data Structures are considered at code-generation time and some are considered at runtime. For the purposes of specification, it is useful to define said data structures:

In a preferred embodiment, the data structures of the Parser and Code Generator comprise the following object oriented software classes: KDBook, KDSheet, KDCell, KDName, KDFunc, KDFuncArg, KDColorScheme, KDEncoder, KDParser, KDCodeSegment, and KDSharedFormula.

In background art spreadsheet applications and components, the global data aspects of a body of spreadsheet data are commonly referred to as a ‘workbook’ or a ‘book’. KDBook is a software Data Structure that represents the global data aspects of a body of spreadsheet data. In a preferred embodiment, KDBook is an object-oriented software class. A singleton instance of KDBook is instantiated.

	Description

Field
Name	The global name of the body of spreadsheet data. The value of
	the Name field is derived from the filename of the body of
	spreadsheet data.
Sheets	Collection of references to KDSheet instances that represent
	the sheets in the body spreadsheet data.
Names	Collection of references to KDName instances that represent
	the named cells or ranges of cells defined in the spreadsheet
	data.
Method
GetCode	A function that assembles the source code representative of
	the global aspects of the body of spreadsheet data.
WriteCode	A function that writes the representative source code to a
	file, the name of which may be specified by the user or
	derived from the filename of the body of spreadsheet data.

KDSheet is a software Data Structure that represents the aspects of a single spreadsheet sheet within a body of spreadsheet data. In background art spreadsheet applications and components, these are commonly referred to as ‘worksheet’ or ‘sheet’. In a preferred embodiment, KDSheet is an object-oriented software class. An instance of KDSheet is instantiated for each sheet in the body of spreadsheet data.

	Description

Field
SheetName	The name of the spreadsheet sheet represented by the
	KDSheet instance.
Index	The one-based index of the spreadsheet sheet repre-
	sented by the KDSheet instance.
Book	A reference to the instance of KDBook that represents
	the global aspects of the body of spreadsheet data.
StartCell	A reference indicating the Top Left cell of the spread-
	sheet sheet for which code is generated. May be set by
	the user to limit the range of cells for which code is
	generated.
EndCell	A reference indicating the Bottom Right cell of the
	spreadsheet sheet for which code is generated. May be
	set by the user to limit the range of cells for which
	code is generated.
Cells	Collection of KDCell instances that represent the cells
	in said sheet.
SharedFormulas	Collection of references to KDSharedFormula
	instances that represent the cell formulas of
	a plurality of spreadsheet cells.
Method
GetCode	A function that assembles the source code repre-
	sentative of the data and calculation aspects of
	the sheet of spreadsheet data represented by the
	instance of KDSheet.
WriteCode	A function that writes the representative source
	code to a file, the name of which may be specified
	by the user or derived from the name of the spread-
	sheet sheet.

KDCell is a software Data Structure that represents the aspects of a single spreadsheet cell within a spreadsheet sheet. In a preferred embodiment, KDCell is an object-oriented software class. An instance of KDCell is instantiated for each cell on said spreadsheet sheet. The KDCell includes the following members.

	Description

Field
Sheet	A reference to the instance of KDSheet that
	represents the aspects of the spreadsheet
	sheet which contains the spreadsheet cell
	represented by the current instance of
	KDCell.
Row	The row of the represented spreadsheet cell.
Col	The column of the represented spreadsheet
	cell.
RC	The text based identifier of the represented
	spreadsheet cell's row and column.
RawFormula	The text of the raw spreadsheet cell formula
	in the syntax of the spreadsheet application.
HasDependents	An indicator of whether other spreadsheet
	cells depend on (refer to) the spreadsheet
	cell represented by the current instance of
	KDCell.
HasDeclaration	An indicator indicating whether a source
	code declaration should be generated for
	the spreadsheet cell represented by the
	current instance of KDCell.
HasFormula	An indicator of whether the spreadsheet
	cell represented by the current instance
	of KDCell contains a cell formula.
Persistent	An indicator of whether the current
	instance of KDCell should be marked as
	persistable.
ForeColor	An indicator of the foreground color of
	the spreadsheet cell represented by the
	current instance of KDCell.
BackColor	An indicator of the background color of the
	spreadsheet cell represented by the current
	instance of KDCell.
FormulaSourceCode	The source code representative formula of
	the spreadsheet cell. Only populated where
	the represented spreadsheet cell contains a
	cell formula rather than a literal data
	value.
CodeSegments	An ordered collection of sub-strings of
	source code segments representative of the
	function calls and parameters in a cell
	formula.
SharedFormula	A reference to an instance of SharedFormula
	(defined below) representative of source
	code called by source code representative
	of cell formulas with similar formula
	structures. Only populated where the repre-
	sented spreadsheet cell contains a cell
	formula similar enough to other cell
	formulas that total source code size can be
	reduced by having the cells call the shared
	formula rather than implement the formula
	individually.
SharedFormulaSourceCode	The source code to call a shared formula
	representative of the cell formula. Only
	populated where the represented spreadsheet
	cell contains a cell formula rather than a
	literal data value.
Method
GetCode	A function that assembles the source code
	representative of the calculation aspects
	of the spreadsheet cell represented by the
	instance of KDCell. The method is only
	executed for cells that contain a formula
	rather than a value.
GetDeclaration	A function that assembles the source code
	representative of the data and identification
	aspects of the spreadsheet cell represented
	by the instance of KDCell.

KDName is a software Data Structure that represents the aspects of a named range of spreadsheet cells within a spreadsheet sheet. In a preferred embodiment, KDName is an object-oriented software class. An instance of KDName is instantiated for each named range of spreadsheet cells within said body of spreadsheet data.

	Description

Field
Name	The text name of the named spreadsheet range represented by
	the KDName instance.
Cell	A reference the KDCell instance representing the single
	spreadsheet cell named by the spreadsheet name represented
	by the current instance of KDName. Only populated for
	spreadsheet names that name a single spreadsheet cell.
TLCell	A reference to the KDCell instance representing the Top Left
	spreadsheet cell of the range of spreadsheet cells named by
	the spreadsheet name represented by the current instance of
	KDName. For spreadsheet names that represent a single
	spreadsheet cell, the KDName.TLCell property is equal to
	the KDName.Cell property.
BRCell	A reference to the KDCell instance representing the Bottom
	Right spreadsheet cell of the range of spreadsheet cells named
	by the spreadsheet name represented by the current instance of
	KDName. For spreadsheet names that represent a single
	spreadsheet cell, the KDName.BRCell property is equal to
	the KDName.Cell property.
RangeRC	The text, in the syntax of the spreadsheet application, that
	specifies the range of spreadsheet cells named by the spread-
	sheet name.
RefersTo	An indicator of whether the represented spreadsheet name
	refers to a single spreadsheet cell or a range of spread-
	sheet cells. One of rtCell, rtVerticalVector,
	rtHorizontalVector, rtMatrix, rtCellList.
Method
<<none>>	In a preferred embodiment, KDName has no member
	methods.

KDFunc is a software Data Structure that represents the aspects of built-in or user-defined spreadsheet functions that can be used in spreadsheet cell formulas. In a preferred embodiment, KDFunc is an object-oriented software class. An instance of KDFunc is instantiated for each supported spreadsheet function. The use of KDFunc allows the present invention to be easily extended to support additional built-in spreadsheet functions and unanticipated user-defined functions by simply adding more instances of KDFunc and KDFuncArg (described below). KDFunc instances representative of built-in spreadsheet functions are included in the invention. KDFunc instances representative of user-defined functions can be dynamically included from an external data source.

Field	Description
SpreadsheetFuncName	The name of the supported function specified in
	the syntax of the spreadsheet application.
TargetCodeFuncName	The name of the supported function specified in
	the syntax of the target software development
	language.
TargetSourceCode	The source code implementation of the supported
	built-in or user-defined spreadsheet function
	specified in the syntax of the target software
	development language.
bUserDefined	A Boolean indicator indicating whether the
	Function is used is user-defined. For built-in
	spreadsheet functions, the value of this
	property is ‘False’. For user-defined
	functions, it is ‘True’.
bUsed	A Boolean indicator indicating whether the
	Function is used in the spreadsheet and there-
	fore requires that the implementation held in
	TargetSourceCode be included in the generated
	source code. The value of bUsed is initially
	‘False’ but is changed to ‘True’ if the function
	is encountered in a spreadsheet cell formula
	during parsing.
Arguments	An ordered Collection of KDFuncArg instances
	that represent the arguments of the represented
	built-in or user-defined spreadsheet function.

KDFuncArg is a software Data Structure that represents the aspects of arguments of built-in or user-defined spreadsheet functions that can be used in spreadsheet cell formulas. In a preferred embodiment, KDFuncArg is an object-oriented software class. An instance of KDFuncArg is instantiated for each argument accepted by each supported spreadsheet function. The use of KDFuncArg allows the present invention to easily support the representation of built-in or user-defined spreadsheet functions that take any number of arguments. Some built-in or user-defined spreadsheet functions take no arguments, some take a fixed number of arguments, some have optional arguments, and some can take a variable-length list of arguments.

Field	Description
Func	A reference to the instance of KDFunc that represents the
	aspects of the built-in or user-defined spreadsheet
	function, an argument of which is represented by the
	current instance of KDFuncArg.
N	The sequence ordinal of the argument represented by the
	current instance of KDFuncArg. For the first argument,
	the value of this property is ‘1’; for the second
	argument, the value of this property is ‘2’, and so on.
ArgumentType	An indicator of the type of argument of the current
	argument of the supported spreadsheet function. One of:
	argCellRef, argExpression, argOptional, or argList.
	argCellRef indicates that the Nth argument must be a
	reference to a spreadsheet cell or a name of a single
	spreadsheet cell.
	argExpression indicates that the Nth argument can be any
	expression that has a value, including a static value,
	a reference to another cell, or a call to another built-in
	or user-defined spreadsheet function.
	argOptional indicates that there may or may not be an
	Nth argument in the built-in or user-defined spreadsheet
	function. If an instance of KDFuncArg is defined with
	ArgumentType = argOptional then every instance of
	KDFuncArg that follows said instance (if any) must have
	its ArgumentType property equal to argOptional.
	argList indicates that the built-in or user-defined
	spreadsheet function takes a variable-length list of
	arguments. If the function takes a variable length list
	of arguments, then one and only one instance of
	KDFuncArg should be instantiated for the built-in or
	user-defined spreadsheet function, and its
	ArgumentType field must be equal to argList.

KDCodeSegment is a software Data Structure that represents the aspects of a segment of code in a cell formula. In a preferred embodiment, KDCodeSegment is an object-oriented software class. An instance of KDCodeSegment is instantiated for each contiguous code segment or parameterizable reference in a cell formula. The use of KDCodeSegment allows the output of present invention to be optimized by identifying spreadsheet cells with cell formulas similar enough that total generated source code size can be reduced by having multiple cells call the shared formula rather than implement the formula individually.

Field	Description
Code	The source code characters in the KDCodeSegment.
Type	An indicator of the type of the KDCodeSegment. One of: segCode,
	segName, segRCRangeRef, or segRCCellRef.
	segCode indicates that the segment is source code.
	segName indicates that the segment represents a reference to a
	named cell or range.
	segRCRangeRef indicates that the segment represents a reference
	to a range of cells.
	segRCCellRef indicates that the segment represents a reference to a
	cell.

KDSharedFormula is a software Data Structure that represents the aspects of a cell formula formation that is common to multiple cells. In a preferred embodiment, KDSharedFormula is an object-oriented software class. An instance of KDSharedFormula is instantiated where at least two cells are similar enough that total generated source code size can be reduced by having multiple cells call a shared formula rather than implement the formula individually.

Field	Description
SharedFormulaName	The name of the source code function repre-
	sented by SharedFormula.
SharedFormulaDefinition	The source code definition of the function
	represented by SharedFormula.

KDColorScheme is a software Data Structure that represents the aspects of a particular combination of colors of spreadsheet cell features. In a preferred embodiment, KDColorScheme is an object-oriented software class. An instance of KDColorScheme is instantiated for each color scheme defined by the user in said body of spreadsheet data. The KDColorScheme allows the user to indicate which spreadsheet cells should be included in code generation, excluded from code generation, and marked as persistent, by specifying the foreground and background colors of the spreadsheet cell.

Field	Description
BackColor	Identifier of the background color of the spreadsheet cell.
ForeColor	Identifier of the foreground (font) color of the spreadsheet
	cell.

KDEncoder is a software Data Structure that represents the aspects of a parser and code generator that generates software source code representative of a body of spreadsheet data. In a preferred embodiment, KDEncoder is an object-oriented software class. A singleton instance of KDEncoder is instantiated to generate said software source code.

	Description

Field
SpreadsheetBook	A reference to a spreadsheet application single-
	ton object that comprises the global aspects of
	the body of spreadsheet data.
Book	A reference to the singleton instance of
	KDBook instantiated to represent the global
	aspects of the body of spreadsheet data.
OutputLocation	The user-specified file system path to the folder
	or directory where generated source code files
	are to be deposited.
PackageName	A preferred embodiment of the present
	invention generates source code that conforms
	to the Java ® software language
	by Sun Microsystems. The
	PackageName field directs that said generated
	software source code contain the user-
	specified PackageName field value as a
	Package descriptor consistent with the
	Package construct of the Java ®
	software language by Sun Microsystems.
ConsiderDependencies	An indicator of whether said source code
	generation process should generate source code
	for all spreadsheet cells that have dependencies
	even if they are otherwise outside of the
	inclusion conditions.
SizeOptimize	An indicator of whether said source code
	generation process should try to reduce the
	size of generated code by replacing individual
	implementations of source code representative
	of similarly structured cell formulas with
	calls to shared functions representative
	of said similarly structured cell formulas.
IncludeColorSchemes	Collection of references to KDColorScheme
	instances that represent all the color schemes
	of spreadsheet cells for which representative
	source code should be generated, even if the
	spreadsheet cells are otherwise outside of the
	inclusion conditions.
ExcludeColorSchemes	Collection of references to KDColorScheme
	instances that represent all the color schemes
	of spreadsheet cells for which representative
	source code should not be generated, even if
	the spreadsheet cells are otherwise in most of
	the inclusion conditions.
PersistentColorSchemes	Collection of references to KDColorScheme
	instances that represent all the color schemes
	of spreadsheet cells for which representative
	source code will be generated and for which
	said representative source code will indicate
	that the cells should be marked as persistent.
Parser	A reference a KDParser instance that is used
	to generate source code representative of
	individual spreadsheet cell formulas.
Method
ConnectBook	A function that instantiates an instance of
	KDBook and connects it via a property
	reference to the spreadsheet application
	singleton object that comprises the global
	aspects of the body of spreadsheet data.
ConnectSheet	A function that is called for each spreadsheet
	sheet in the body of spreadsheet data to
	instantiate an instance of KDSheet and
	connect it via a property reference to the
	represented spreadsheet sheet. The properties
	of the KDSheet instances are also populated
	with relevant fields that describe the spread-
	sheet sheet, and with a reference to the single-
	ton instantiated KDBook instance.
ConnectNames	A function that is called for each spreadsheet
	name in the body of spreadsheet data to
	instantiate an instance of KDName and connect
	it via a property reference to the represented
	spreadsheet name. The properties of the
	KDName instances are also populated with
	relevant fields that describe the spreadsheet
	name, and with a reference to the singleton
	instantiated KDBook instance.
GetColorSchemes	A function that searches the body of spread-
	sheet data for user-defined color schemes that
	indicate which cells are to be included,
	excluded, and or marked as persistent in the
	generated source code. An instance of
	KDColorScheme is instantiated and stored
	in the corresponding KDEncoder field for
	each color scheme found.
ParseCellFormulas	A function that iterates through each spread-
	sheet sheet and each spreadsheet cell within
	said sheet to generate and store the source
	code representative of the cell formula for
	each of said spreadsheet cells.
WriteCode	A function that writes the generated source
	code representative of the body of spreadsheet
	data to files in the said OutputLocation.
DeployCode	A function that further processes said
	generated source code to prepare it for
	deployment in a target execution environment.

KDParser is a software Data Structure that represents aspects of a recursive descent expression parser that parses spreadsheet cell formulas and generates software source code representative of the calculations and data transformations of said spreadsheet cell formulas. In a preferred embodiment, KDParser is an object-oriented software class. A singleton instance of KDParser is instantiated to parse said cell formulas and generate said representative source code, All cell formula parsing functionality is embodied in this class. In a preferred embodiment, KDParser panes a cell formula and generates source code conforming to the grammar and syntax of a software development language, such as the Java® language by Sun Microsystems. Various derivations of KDParser support various target software development languages, such as Visual Basic®, VBScript®, Jscript® and Microsoft Visual Basic® for Applications by Microsoft, Basic, Assembler, C++, C#, Fortran, COBOL and other existing arid unanticipated target software development languages.

	Description

Field
Funcs	A collection of KDFunc instances that
	represent the built-in and user-defined spread-
	sheet functions.
Method
Encode	Function that parses a complete spread-
	sheet cell formula and generates representative
	source code in a target software development
	language. Calls GetSubExprSourceCode for
	subexpressions within cell formula.
GetSubExprSourceCode	Recursive method that parses arbitrary-
	depth nested subexpressions in spreadsheet
	cell formulas.
GetTok	Method that isolates tokens within sub
	expressions of cell formulas.
ParseFunc	Method that parses and generates repre-
	sentative source code for built-in and user-
	defined spreadsheet functions.
ParseArgs	Method that parses and generates repre-
	sentative source code for arguments within
	built-in and user-defined spreadsheet
	functions.
ParseArgList	Method that parses and generates repre-
	sentative source code for arguments within
	built-in and user-defined spreadsheet
	functions where said spreadsheet function
	accepts a variable-length list of
	arguments.

In a preferred embodiment, the data structures of the Calculation Engine comprise the following object oriented software classes: IKDJEngine, KDJEngine, KDJObject, KDJWorkbook, ‘MyWorkbook’ book, KDJWorksheet, ‘MyWorksheet’ sheet, KDJCell, KDJRange, KDJValue, and KDJExpressionParser, KDJCalcException, KDJFunctionLibrary, and KDJUserDefinedFunctionLibrary.

KDJEngine is a software Data Structure and functions that together represent aspects of a Calculation Engine. KDJEngine implements a public application programming interface (API) that make features of the invention available to calling applications. The methods are directed at loading, getting, and setting values, among other operations. In a preferred embodiment, KDJEngine is an object-oriented software class. A singleton instance of KDJEngine is instantiated at runtime. Note that the list of methods exposed of KDJEngine is exemplary.

	Description

Field
<<none>>	In a preferred embodiment, KDJEngine has no
	fields.
Method
getCalcEngine	A method which takes in an identifier of the
	generated source code and returns an instance of the
	Calculation Engine to work with
forceRecalc	A method which forces the Calculation Engine
	to mark the KDJWorkbook dirty so that all
	instantiations representing spreadsheet cells
	with formulas are recalculated.
getActiveSheet	A method which returns an identifier of the active
	instance of KDJWorksheet (defined below).
setActiveSheet	A method which activates an instance of
	KDJWorksheet.
getSheetName	A method which takes in a numeric identifier and
	returns the name of the represented worksheet.
getSheetNumber	A method which takes in the name of a represented
	worksheet and returns a numeric identifier of the
	represented active worksheet.
getCellText	A method that takes in a row and column to return
	the text interpretation of the represented cell's
	value on the represented active worksheet.
setCellText	A method that takes in a row identifier, column
	identifier, and text value and sets the represented
	cell's value on the represented active
	worksheet.
getCellNumber	A method that takes in row and column identifiers
	to return the numeric (double) interpretation of the
	corresponding represented cell's value on the
	represented active sheet.
setCellNumber	A method that takes in a row identifier, a column
	identifier, and a numeric (double) value and sets
	the represented cell's value on the represented
	active worksheet.
getCellLogical	A method that takes in row and column identifiers
	to return the Boolean (double) interpretation of
	the corresponding represented cell's value on the
	represented worksheet.
setCellLogical	A method that takes in a row identifier, a column
	identifier, and a Boolean value and sets the repre-
	sented cell's value on the represented active
	worksheet.
getRangeFromName	A method that takes in a name identifier and returns
	a KDJRange instance that represents the cell or cells
	associated with the name.
getInputCells	A method which returns a collection of KDJCell
	instances which are used for input operations only.
	These are indexed by A1 notation.
getOutputCells	A method which returns a collection of KDJCell
	instances which are used for output operations only.
	These are indexed by A1 notation.
getPersistentCells	A method which returns a collection of the KDJCell
	instances which are marked as persistent. These are
	indexed by A1 notation.
getSheetCount	A method which returns the number of represented
	worksheets in the represented workbook.
clearCell	A method that takes in row and column identifiers
	and clears the value of the represented cell.
clearRange	A method which takes in a range identifier and
	clears the values in the represented cells.
hasFormula	A method which takes in row and column identifiers
	and returns an indicator of whether the represented
	cell contains a cell formula.

In a preferred embodiment, KDJObject is an object-oriented software class that has no member data fields or methods, but acts as the root-most class in an inheritance hierarchy. KDJValue, KDJRange, and KDJCell all inherit from KDJObject. Instances of KDJObject are not instantiated directly.

	Description

Field
<<none>>	In a preferred embodiment, KDJObject has no member fields.
Method
<<none>>	In a preferred embodiment, KDJObject has no member
	methods.

In background art spreadsheet applications and components, the global data aspects of a body of spreadsheet data are commonly referred to as a ‘workbook’ or a ‘book’. In the present invention, KDJWorkbook is a software Data Structure and functions defined in the target software development language that together represent the global, general data and behavior aspects of a body of spreadsheet data at runtime. In a preferred embodiment, KDJWorkbook is an object-oriented software class from which classes representative of specific spreadsheet workbooks are derived. KDJWorkbook inherits from KDJEngine. KDJWorkbook is not instantiated at runtime.

	Description

Field
Sheets	A collection of references to the contained
	KDJWorksheet instances.
ActiveSheet	A reference to the active KDJWorksheet instance.
Names	A collection of data structures representing named
	spreadsheet cells and ranges of spreadsheet cells.
dirtyCount	A numeric counter that keeps track of the instance of
	KDJWorkbook's state. Each KDJCell object has a
	corresponding dirtyCount. If the count on the KDJCell
	is not equal to the dirtyCount on the KDJWorkbook,
	then the formula attached to the KDJCell must be
	recalculated. The dirtyCount is incremented every
	time a KDJCell value is set through KDJEngine.
Method
addNamedCell	A method which takes in a name and a KDJCell
	reference and makes an association on the
	KDJWorkbook that the name refers to the KDJCell
	instance.
addNamedRange	A method which takes in a name and KDJRange
	reference and makes an association on the book
	that the name refers to the KDJRange.
addSheet	A method that takes in a KDJWorksheet reference,
	a position, and a name and adds a KDJWorksheet
	reference to the KDJWorkbook.
setRecalc	A method which increments the dirtyCount to indicate
	that KDJCell instances representing spreadsheet
	cells with formulas need to be recalculated.

‘MyWorkbook’book is a software Data Structure and functions defined in the target software development language that together represent global data and behavior aspects of a specific body of spreadsheet data at runtime in the present invention. In a preferred embodiment, ‘MyWorkbook’book is an object-oriented software class that is derived from KDJWorkbook. The source code of this class is generated by the Parser and Code Generator to represent the global data and behavior aspects of a specific body of spreadsheet data. In a preferred embodiment, ‘MyWorkbook’ is derived from the name of a spreadsheet workbook, so if the spreadsheet workbook's name is ‘Financials’ then the name of the generated class is ‘Financialsbook’. A singleton instance of ‘MyWorkbook’book is instantiated at runtime.

	Description

Field
‘myWorksheet1’sheet	An instantiation of the generated source code
. . .	containing the values and formulas in
‘myWorksheetN’sheet	myWorksheet1.
Method
<<Constructor>>	Sets the default active KDJWorksheet instance
	and adds all of the named KDJCell instances and
	KDJRange instances KDJWorkbook.Names.

KDJWorksheet is a software Data Structure that represents the aspects of a single spreadsheet sheet within a body of spreadsheet data. In background art spreadsheet applications and components, these are commonly referred to as ‘worksheet’ or ‘sheet’. In the present invention, KDJWorksheet is a software Data Structure and functions defined in the target software development language that together represent the general data and behavior aspects of a of a single spreadsheet sheet at runtime. In a preferred embodiment, KDJWorksheet is an object-oriented software class from which classes representative of specific spreadsheet sheets are derived. KDJWorksheet is not instantiated at runtime.

	Description

Field
sheetName	The name of the spreadsheet sheet represented by the
	KDSheet instance.
sheetIndex	The one-based index of the spreadsheet sheet repre-
	sented by the KDSheet instance.
columns	A collection of data structures representing the
	columns of the spreadsheet. Each representative
	column comprises a collection of data structures
	that represent the rows in the column data.
Method
addCellReference	A method which takes in a reference to an instance
	of KDJCell and row and column identifiers to add
	the reference to the KDJWorksheet.columns
	collection.
getCell	A method which takes in row and column identifiers
	and returns a reference to the KDJCell instance
	at that location.
getRange	A method which takes in top left row, top left
	column, bottom right row, bottom right column
	identifiers and returns a reference to the
	KDJRange instance at that location.
getValue	A method which takes in a native-type value such
	as a double, Boolean, or String and returns a
	KDJValue instance initialized to the input value.
getCellValue	A method which takes in row and column identifiers
	to return the KDJValue instance representing the
	value of the referenced KDJCell instance.
rowColToA1	A method that takes in row and column identifiers and
	returns a String representing the row and column in
	A1 notation. For example, the call rowColToA1(1,1)
	would return the string “A1”.

‘MyWorkbook’book is a software Data Structure and functions defined in the target software development language that together represent data and behavior aspects of a specific spreadsheet sheet at runtime in the present invention. In a preferred embodiment, ‘MyWorksheet’sheet is an object-oriented software class that is derived from KDJWorksheet. The source code of this class is generated by the Parser and Code Generator to represent the data and behavior aspects of a specific spreadsheet sheet. In a preferred embodiment, ‘MyWorksheet’ is derived from the name of a spreadsheet sheet, so if the spreadsheet sheet is named ‘Revenue’ then the name of the generated class would be ‘Revenuesheet.’ An instance of ‘MyWorksheet’sheet is instantiated at runtime for each spreadsheet sheet in the spreadsheet workbook.

	Description

Field
‘MyWorksheet’book	A reference to the instance of KDJBook that repre-
	sents the global aspects of the body of spreadsheet
	data.
A1	A reference to the KDJCell instance at row, column
. . .	location 1,1 with the specified initial value. For
IVN	example, if the represented spreadsheet sheet
	contains a cell B3 that contains a literal value
	rather than a cell formula, then the representative
	‘MyWorksheet’sheet class will have a member
	‘B3’ of type KDJCell.
Method
<<Constructor>>	Creates the parent-child relationship between the
	KDJWorkbook and KDJWorksheet.
B1e	A method which representing the formula contained
. . .	in the cell and returns a resultant Value instance. For
IUNe	example, if the represented spreadsheet sheet
	contains a cell B4 that contains a cell formula
	rather than a literal value, then the repre-
	sentative ‘MyWorksheet’sheet class will have a
	member method ‘B4e’ that returns an instance of
	KDJValue.

KDJCell is a software Data Structure and functions defined in the target software development language that together represent data and behavior aspects of a spreadsheet cell at runtime in the present invention. In a preferred embodiment, KDJCell is an object-oriented software class. Source code declaring a static instance of this class is generated by the present invention to represent the data aspects of each spreadsheet cell that contains a literal value rather than a cell formula. Instances of KDJCell are instantiated at runtime by the present invention to represent data and behavior aspects of each spreadsheet cell that contains a cell formula rather than a literal value.

	Description

Field
Sheet	A reference to the instance of ‘MyWorksheet’sheet that
	represents the aspects of the spreadsheet sheet which con-
	tains the spreadsheet cell represented by the current instance
	of KDJCell.
Row	Read-only property containing the row of the represented
	spreadsheet cell.
Col	Read-only property containing the column of the repre-
	sented spreadsheet cell.
value	A reference to a KDJValue object that stores the text,
	numeric, Boolean, or error values for a cell.
persistent	An indicator of whether the current instance of KDCell
	should be marked as persistable.
hasFormula	An indicator of whether or not the cell has a formula
	associated with it.
dirtyCount	A numeric counter that keeps track of the cell's state.
	If the count on the cell is not equal to the dirtyCount on
	the workbook, then the formula attached to the cell must be
	recalculated.
Method
getValue	A method which returns the KDJValue of the KDJCell
	instance. If the KDJCell's dirtyCount is not equal to the
	dirtyCount on the KDJWorkbook, then the formula is
	recalculated on request, otherwise, a cached result is
	returned.
setValue	Sets the value reference of the KDJCell instance.
clear	A method which clears the KDJCell's value.
getText	A method which returns the text representation of
	the KDJCell's KDJValue.
setText	A method that takes in a string and sets the KDJCell's
	KDJValue to the input string.
getNumber	A method which returns the numeric (double) repre-
	sentation of the KDJCell's KDJValue.
setNumber	A method that takes in a number (double) and sets the
	KDJCell's KDJValue to the input number.
getLogical	A method which returns the Boolean representation of the
	KDJCell's KDJValue.
setLogical	A method that takes in a Boolean and sets the KDJCell's
	KDJValue to the input Boolean value.
getError	A method which returns the Error representation of the
	KDJCell's KDJValue.

KDJRange is a software Data Structure and functions defined in the target software development language that together represent data and behavior aspects of a range of spreadsheet cells within a spreadsheet sheet. In a preferred embodiment, KDJRange is an object-oriented software class. Instances of KDJRange are instantiated at runtime.

	Description

Field
topLeftRow	An identifier of the location of the KDJRange
	instance's top left row.
topLeftColumn	An identifier of the location of the KDJRange
	instance's top left column.
bottomRightRow	An identifier of the location of the KDJRange
	instance's bottom right row.
bottomRightColumn	An identifier of the location of the KDJRange
	instance's bottom right column.
type	An indicator of whether the represented spread-
	sheet name refers to a single spreadsheet cell or
	a range of spreadsheet cells. One of cellType,
	verticalVectorType, horizontalVectorType,
	matrixType.
Method
equals	A method which takes in two references to
	KDJRange instances and compares them for
	equality.

KDJValue is a software Data Structure and functions defined in the target software development language that together represent data and behavior aspects of a KDJCell's value evaluation, whether the cell contains a literal value or a cell formula. KDJValue is also used to represent the results of built-in spreadsheet functions and user-defined functions. In a preferred embodiment, KDJValue is an object-oriented software class. Instances of KDJValue are instantiated at runtime.

	Description

Field
number	A number (double) which stores the numeric representation
	of the KDJValue.
text	A string which stores the text representation of the
	KDJValue.
bool	A Boolean which stores the Boolean representation of
	the KDJValue.
error	A KDJException which stores an Errors associated with the
	KDJValue if there is one.
lastSet	An indicator that represents what type of value that was
	last set. One of noneType, numberType, textType,
	booleanType, or errorType.
logicalValue	An indicator which stores whether the KDJValue represents
	a Boolean value or not.
reference	An indicator which stores whether the KDJValue is a
	reference to a KDJCell's KDJValue or not.
Method
compareTo	A method that takes in a KDJValue and performs a
	comparison of the current instance of the KDJValue with
	another. It attempts to perform a numeric comparison and
	returns −1 if the parameter is less than the value, 0
	is if it is equal to, or 1 if it is greater than. If it
	cannot perform a numeric or Boolean comparison, it
	performs a lexicographical comparison of the strings
	based on Unicode character values.
clone	A method which makes a duplicate KDJValue object in a
	new memory space.

KDJCalcException is a software Data Structure and functions that represent aspects of an Exception. In a preferred embodiment, KDJCalcException is an object-oriented software class. Instances of KDJCalcException are instantiated at runtime when an error occurs as the result of any unexpected conditions.

	Description

Field
type	An indicator that tells which type of error has occurred. The
	error types are NULL_ERR, DIV0_ERR, VALUE_ERR,
	REF_ERR, NAME_ERR, and NA_ERR.
Method
	In a preferred embodiment, KDJCalcException has no member
	methods.

KDJExpressionParser is a software Data Structure and functions that represent the aspects of an expression parser for use by run-time implementations of built-in spreadsheet functions and user-defined functions that can take quoted regular expressions as arguments. In a preferred embodiment, KDJExpressionParser is an object-oriented software class. Instance of KDJExpressionParser are instantiated at runtime during evaluation of functions such as ‘SUMIF’ and ‘COUNTIF’, for example.

	Description

Field
compVal	A KDJValue instance which stores the value that is
	going to be compared.
comparison	The type of comparison being done, EQUAL,
	NOT_EQUAL, LESS_THAN, LESS_OR_EQUAL,
	GREATER_THAN, or GREATER_OR_EQUAL.
Method
<<Constructor>>	A constructor that takes in a KDJValue object
	containing a string which has a comparison operator
	and a value for example “>=4”.
	GREATER_OR_EQUAL becomes the comparison
	and compVal is 4.
compareTo	Compares the KDJValue instance to the compVal
	based on the comparison criteria and returns true if
	the criteria are met.

KDJFunctionLibrary is a set of functions defined in the target software development language that represent behavior aspects necessary for execution of built-in spreadsheet functions. In a preferred embodiment, KDJFunctionLibrary is an object-oriented software class. All member functions of KDJFunctionLibrary are static and require no instantiation. In a preferred embodiment, KDJFunctionLibrary can be generated and only include implementations of the built-in spreadsheet functions actually used in the specific workbook for which code is generated. This serves to optimize the generated code for size. The entire library of built-in spreadsheet functions can be used if the Calculation Engine is to be shared by modules representing several workbooks, where the used functions may not be known at code-generation-time.

Note: The following list of built-in spreadsheet functions and descriptions contemplated byte invention is in spreadsheet syntax format as defined within the Help System of Microsoft® Excel 2000, a background art spreadsheet application.

	Description

Field
<<none>>	In a preferred embodiment, KDJFunctions has no fields.
Method
Operators:
+	Addition operator, returns the result of adding a number to a number.
−	Subtraction operator, returns the result of a number subtracted from another
	number.
*	Multiplication operator, returns the result of multiplying a number by a number.
/	Division operator, returns the result of a number divided by a number.
{circumflex over ( )}	Raise-to-the-power operator, returns the result of a number raised to a power
%	Percent operator, returns the percent of a number (the number multiplied by
	0.01).
=	Equivalence comparator compares two values and returns TRUE if they are
	exactly the same, FALSE otherwise
>	Greater-than comparator, compares two values and returns TRUE if value 1 is
	greater than value 2, FALSE otherwise
<	Less-than comparator, compares two values and returns TRUE if value 1 is less
	than value 2, FALSE otherwise
>=	Greater-than-or-equal-to comparator, compares two values and returns TRUE if
	value 1 is greater than or equal to value 2, FALSE otherwise
<=	Less-than-or-equal-to comparator, compares two values and returns TRUE if
	value 1 is less than or equal to value 2, FALSE otherwise
<>	Not-equal comparator, compares two values and returns FALSE if the values are
	equal, TRUE otherwise
&	String join operator, joins two text strings into one text string and returns this
	string
Functions:
ABS	Returns the absolute value of a number
ACOS	Returns the arccosine of a number
ACOSH	Returns the inverse hyperbolic cosine of a number
ADDRESS	Creates a cell address as text, given the specified row and colunm numbers
AND	Returns TRUE if all arguments are true; otherwise, returns FALSE if one
	argument is false.
AREAS	Returns the number of areas in a reference
ASIN	Returns the arcsine of a number
ASINH	Returns the inverse hyperbolic sine of a number
ATAN	Returns the arctangent of a number
ATAN2	Returns the arctangent from x- and y- coordinates
ATANH	Returns the inverse hyperbolic tangent of a number
AVEDEV	Returns the average of the absolute deviations of the list of arguments
AVERAGE	The average of the values in a list.
AVERAGEA	Mean with text treated as 0 except TRUE = 1
BETADIST	Returns the cumulative beta probability density function according to the
	specified parameters
BETAINV	Returns the inverse of the cumulative beta probability density function
BINOMDIST	Returns the individual term binomial distribution probability
CALL	Calls a procedure in a dynamic link library or code resource.
CEILING	Rounds a number to the nearest integer or to the nearest multiple of significance
CELL	Returns information about the formatting, location, or contents of the upper-left
	cell in a reference
CHAR	Returns the character specified by a number
CHIDIST	Returns the one-tailed probability of the chi-squared distribution
CHIINV	Returns the inverse of the one-tailed probability of the chi-squared distribution
CHITEST	Returns the value from the chi-squared (γ2) distribution for the statistic and the
	appropriate degrees of freedom
CHOOSE	Return the value specified by index number from the list of value arguments
CLEAN	Removes all nonprintable characters from text
CODE	Returns a numeric code, which corresponds to the character set used by your
	computer, for the first character in a text string
COLUMN	Returns the column number of the given reference
COLUMNS	Returns the number of columns in an array or reference
COMBIN	Returns the number of combinations for a given number of objects
CONCATENATE	Joins several text strings into one text string and returns this string
CONFIDENCE	Returns the confidence interval for a population mean
CORREL	Returns the correlation coefficient of the array1 and array2 cell ranges
COS	Returns the cosine of a number
COSH	Returns the hyperbolic cosine of a number
COUNT	The number of items in a list. This is the default function for nonnumeric data.
COUNTA	Counts the number of cells that are not empty and the values within the list of
	arguments
COUNTBLANK	Counts empty cells in a specified range of cells
COUNTIF	Counts the number of nonblank cells within a range that meet the given criteria
COVAR	Returns covariance, the average of the products of deviations for each data point
	pair in two data sets
CRITBINOM	Returns the smallest value for which the cumulative binomial distribution is
	greater than or equal to a criterion value
DATE	Returns the serial number that represents a particular date
DATEVALUE	Returns the serial number of the date represented by the text argument
DAVERAGE	Returns the average of selected database entries
DAY	Returns the day of a date, represented by a serial number
DAYS360	Returns the number of days between two dates based on a 360-day year (twelve
	30-day months)
DB	Returns the depreciation of an asset for a specified period using the fixed-
	declining balance method.
DCOUNT	Counts the cells that contain numbers in a database
DCOUNTA	Counts nonblank cells in a database
DDB	Returns the depreciation of an asset for a specified period using the double-
	declining balance method or some other method you specify.
DEGREES	Converts radians into degrees.
DEVSQ	Returns the sum of squares of deviations of the arguments from their sample
	mean
DGET	Extracts from a database a single record that matches the specified criteria
DMAX	Returns the maximum value from selected database entries
DMIN	Returns the minimum value from selected database entries
DOLLAR	Converts a number to text using currency format, with the decimals rounded to
	the specified place
DPRODUCT	Multiplies the values in a particular field of records that match the criteria in a
	database
DSTDEV	Estimates the standard deviation based on a sample of selected database entries
DSTDEVP	Calculates the standard deviation based on the entire population of selected
	database entries
DSUM	Adds the numbers in the field column of records in the database that match the
	criteria
DVAR	Estimates variance based on a sample from selected database entries
DVARP	Calculates variance based on the entire population of selected database entries
ERRORTYPE	Returns a number corresponding to one of the error values in KDJCalcException
	or returns the #N/A error if no error exists for the argument value
EVEN	Rounds a number up to the nearest even integer
EXACT	Compares two text strings and returns TRUE if they are exactly the same,
	FALSE otherwise
EXP	Returns e raised to the power of a given number
EXPONDIST	Returns the exponential distribution of a function
FACT	Returns the factorial of a number
FACTDOUBLE	Returns the double factorial of a number
FALSE	Returns the logical value FALSE
FDIST	Returns the F probability distribution
FINV	Returns the inverse of the F probability distribution
FISHER	Returns the Fisher transformation at x
FISHERINV	Returns the inverse of the Fisher transformation
FIND	FIND finds one text string (the first argument) within another text string (the
	second argument), and returns the number of the starting position of the first
	argument, from the first character of the second argument
FIXED	Rounds a number to the specified number of decimals, formats the number in
	decimal format either using or not using a period and commas, and returns the
	result as text
FLOOR	Rounds a number down, towards zero, to the nearest multiple of significance
FORECAST	Calculates, or predicts, a future value by using existing values
FREQUENCY	Calculates how often values occur within a range of values, and then returns a
	vertical array of numbers
FTEST	Returns the result of an F-test on the two array arguments
FV	Returns the future value of an investment based on periodic, constant payments
	and a constant interest rate
GAMMADIST	Returns the gamma distribution
GAMMAINV	Returns the inverse of the gamma cumulative distribution
GAMMALN	Returns the natural logarithm of the gamma function, Γ(x), on argument x
GCD	Returns the greatest common divisor
GEOMEAN	Returns the geometric mean of an array or range of positive data
GETPIVOTDATA	Returns data stored in a PivotTable
GROWTH	Calculates predicted exponential growth by using existing data
HARMEAN	Returns the harmonic mean of a data set
HLOOKUP	Searches for the first argument value in the top row of the specified table or
	array of values, and then returns a value in the same column from a row you
	specify in the table or array
HOUR	Returns the hour, in integer format ranging from 0 to 23, of a time value
HYPGEOMDIST	Returns the probability of a given number of sample successes, given the sample
	size, population successes, and population size
IF	Returns 1st value if True, otherwise returns logical value FALSE
IF	Returns 1st value if True, otherwise returns 2nd Value
INDEX	Returns the value of a specified cell or array of cells within array
INDEX	Returns the value of a specified cell or array of cells within array
INDEX	Returns a reference to a specified cell or cells within reference
INDIRECT	Returns the reference specified by the argument text string
INFO	Returns information about the formatting, location, or contents of the upper-left
	cell in a reference
TNT	Rounds a number down to the nearest integer
INTERCEPT	Calculates the point at which a line will intersect the y-axis by using existing x-
	values and y-values
IPMT	Returns the interest payment for a given period for an investment based on
	periodic, constant payments and a constant interest rate
IRR	Returns the internal rate of return for a series of cash flows represented by the
	numbers in the values of the argument
ISBLANK	Returns the logical value TRUE if the argument is a reference to an empty cell;
	otherwise it returns FALSE
ISERR	Returns the logical value TRUE if the argument is a reference to any error value
	except #N/A; otherwise it returns FALSE
ISERROR	Returns the logical value TRUE if the argument is a reference to any error value;
	otherwise it returns FALSE
ISLOGICAL	Returns the logical value TRUE if the argument is a reference to a logical value;
	otherwise it returns FALSE
ISNA	Returns the logical value TRUE if the argument is a reference to the #N/A error
	value; otherwise it returns FALSE
ISNONTEXT	Returns the logical value TRUE if the argument is a reference to any item that is
	not text; otherwise it returns FALSE
ISNUMBER	Returns the logical value TRUE if the argument is a reference to a number;
	otherwise it returns FALSE
ISPMT	Calculates the interest paid during a specific period of an investment
ISREF	Returns the logical value TRUE if the argument is a reference to a reference;
	otherwise it returns FALSE
ISTEXT	Returns the logical value TRUE if the argument is a reference to text; otherwise
	it returns FALSE
KURT	Returns kurtosis of a data set.
LARGE	Returns the k-th largest value in a data set, where the data set is specified by the
	first argument and the value of k by the second argument
LCM	Returns the least common multiple
LEFT	Returns the first character or characters in the argument text string, based on the
	number of characters you specify
LEN	Returns the number of characters in the argument text string
LINEST	Calculates the statistics for a line by using the “least squares” method to
	calculate a straight line that best fits your data, and returns an array that
	describes the line
LN	Returns the natural logarithm of a number.
LOG	Returns the logarithm of a number to the base 10
LOG	Returns the logarithm of a number to a specified base
LOG10	Returns the base-10 logarithm of a number
LOGEST	Calculates an exponential curve that fits your data and returns an array of values
	that describes the curve
LOGINV	Returns the inverse of the lognormal cumulative distribution function of x,
	where ln(x) is normally distributed with parameters mean and standard_dev
LOGNORMDIST	Returns the cumulative lognormal distribution of x, where ln(x) is normally
	distributed with parameters mean and standard_dev
LOOKUP	Returns value from one-row, one-col range or an array.
LOOKUP	Looks in a one-row or one-column range (known as a vector) for a value and
	returns a value from the same position in a second one-row or one-column range
LOWER	Converts all uppercase letters in the argument text string to lowercase
MATCH	Returns the relative position of an item in an array that matches a specified value
	in a specified order
MAX	Returns the largest value in a set of values. Ignores logical values and text.
MAXA	Returns the largest value in a set of values. Does not ignore logical values and
	text.
MDETERM	Returns the matrix determinant of an array
MEDIAN	Returns the median of the given numbers
MID	Returns a specific number of characters from the argument text string, starting at
	the specified position, based on the specified number of characters
MIN	Returns the smallest value in a set of values. Ignores logical values and text.
MINA	Returns the smallest value in a set of values. Does not ignore logical values and
	text.
MINUTE	Returns the minutes, in integer format ranging from 0 to 59, of a time value
MINVERSE	Returns the matrix inverse of an array
MIRR	Returns the modified internal rate of return for a series of periodic cash flows
MMULT	Returns the matrix product of two arrays
MOD	Returns the remainder from division
MODE	Returns the most frequently occurring value in an array or range of data
MONTH	Returns the month, in integer format ranging from 0 to 12, of a date represented
	by a serial number
MROUND	Returns a number rounded to the desired multiple
MULTINOMIAL	Returns the multinomial of a set of numbers
N	Returns a value converted to a number
NA	Returns the error value #N/A
NEGBINOMDIST	Returns the probability that there will be number_f failures before the number_s-
	th success, when the constant probability of a success is probability_s
NORMDIST	Returns the normal cumulative distribution of the argument value for the
	specified mean and standard deviation
NORMINV	Returns the inverse of the normal cumulative distribution for the specified mean
	and standard deviation
NORMSDIST	Returns the standard normal cumulative distribution function for a value
NORMSINV	Returns the inverse of the standard normal cumulative distribution
NOT	Reverses the value of its argument
NOW	Returns the serial number of the current date and time
NPER	Returns the number of periods for an investment based on periodic, constant
	payments and a constant interest rate
NPV	Calculates the net present value of an investment by using a discount rate and a
	series of future payments (negative values) and income (positive values)
ODD	Rounds a number up to the nearest odd integer
OFFSET	Returns a reference to a range that is a specified number of rows and columns
	from a cell or range of cells
OFFSET	Returns a reference to a range that is a specified number of rows and columns
	from a cell or range of cells and has a specified height
OFFSET	Returns a reference to a range that is a specified number of rows and columns
	from a cell or range of cells and has a specified height and width
OR	Returns TRUE if any argument is TRUE; returns FALSE if all arguments are
	FALSE
PEARSON	Returns the Pearson product moment correlation coefficient given two data sets
PERCENTILE	Given a data range and a value k, returns the k-th percentile of values in the
	range
PERCENTRANK	Returns the rank of a value in a data set as a percentage of the data set
PERMUT	Returns the number of permutations for a given number of objects that can be
	selected from number objects
PI	Returns the value of Pi
PMT	Calculates the payment for a loan based on constant payments and a constant
	interest rate
POISSON	Returns the Poisson distribution
POWER	Returns the result of a number raised to a power
PPMT	Returns the payment on the principal for a given period for an investment based
	on periodic, constant payments and a constant interest rate
PROB	Returns the probability that values in a range are between two limits
PRODUCT	Multiplies its arguments
PROPER	Capitalizes the first letter in the given text string and any other letters in the text
	that follow any character other than a letter. Converts all other letters to
	lowercase letters
PV	Returns the present value of an investment
QUARTILE	Returns the specified quartile of a data set
QUOTIENT	Returns the integer portion of a division
RADIANS	Converts degrees to radians
RAND	Returns a random number between 0 and 1
RANDBETWEEN	Returns a random number between the numbers you specify
RANK	Returns the rank of a number in a list of numbers
RATE	Returns the interest rate per period of an annuity
REPLACE	Replaces part of a text string, based on the number of characters you specify,
	with a different text string
REPT	Returns the given text repeated the specified number of times
RIGHT	Returns the last character or characters in a text string, based on the number of
	characters you specify
ROMAN	Converts an Arabic numeral to roman, as text
ROUND	Rounds a number to a specified number of digits
ROUNDDOWN	Rounds a number down, toward zero
ROUNDUP	Rounds a number up, away from zero
ROW	Returns the row number of a reference
ROWS	Returns the number of rows in a reference or array
RSQ	Returns the square of the Pearson product moment correlation coefficient
	through data points in the specified ranges of data points
SEARCH	Returns the number of the character at which a specific character or text string is
	first found, beginning with the specified number
SECOND	Returns the seconds of a time value
SERIESSUM	Returns the sum of a power series based on the formula
SIGN	Returns the sign of a number
SIN	Returns the sine of the given angle
SINH	Returns the hyperbolic sine of a number
SKEW	Returns the skewness of a distribution
SLN	Returns the straight-line depreciation of an asset for one period
SLOPE	Returns the slope of the linear regression line through data points in the specified
	ranges of data points
SMALL	Given a data set and a value k, returns the k-th smallest value in the data set
SQRT	Returns a positive square root
SQRTPI	Returns the square root of (number * Pi)
STANDARDIZE	Returns a normalized value from a distribution characterized by mean and
	standard deviation
STDEV	Estimates standard deviation based on a sample
STDEVA	Estimates standard deviation based on a sample, and includes all text and logical
	values in its calculation
STDEVP	Calculates standard deviation based on the entire population given as arguments
STDEVPA	Calculates standard deviation based on the entire population given as arguments,
	including text and logical values
STEYX	Given a range of dependent data points(y's) and a range of independent data
	points(x's), returns the standard error of the predicted y-value for each x in the
	regression
SUBSTITUTE	Substitutes new text for old text in a given text string
SUBTOTAL	Returns a subtotal in a list or database
SUM	The sum of the values in a list. This is the default function for numeric data.
SUMIF	Adds the cells specified by a given criteria
SUMIF	Adds the cells coinciding with the cells specified by a given criteria
SUMPRODUCT	Returns the sum of the products of corresponding array components
SUMSQ	Returns the sum of the squares of the arguments
SUMX2MY2	Returns the sum of the difference of squares of corresponding values in two
	arrays
SUMX2PY2	Returns the sum of the sum of squares of corresponding values in two arrays
SUMXMY2	Returns the sum of squares of differences of corresponding values in two arrays
SYD	Returns the sum-of-years' digits depreciation of an asset for a specified period
T	Returns the text referred to by the given value
TAN	Returns the tangent of a number
TANH	Returns the hyperbolic tangent of a number
TDIST	Returns the Percentage Points (probability) for the Student t-distribution where a
	numeric value (x) is a calculated value of t for which the Percentage Points are to
	be computed
TEXT	Converts a given value to text in a specific number format
TIME	Returns the decimal number for a particular time represented by an hour, minute,
	and second value
TIMEVALUE	Returns the decimal number of the time represented by a text string
TINV	Returns the t-value of the Student's t-distribution as a function of the probability
	and the degrees of freedom
TODAY	Returns the serial number of the current date
TRANSPOSE	Returns a vertical range of cells as a horizontal range, or vice versa
TREND	Fits a straight line (using the method of least squares) to the given arrays of y-
	values and x-values. Returns the y-values along that line for the array of new x
	values that you specify
TRIM	Truncates a number to an integer by removing the fractional part of the number
TRIMMEAN	Returns the mean of the interior of a data set
TRUE	Returns the logical value TRUE
TRUNC	Truncates a number to an integer
TTEST	Returns the probability associated with a Student's t-Test
TYPE	Returns the type of a value
UPPER	Converts the given text to uppercase
VALUE	Converts a text string that represents a number into a number.
VAR	Estimates variance based on a sample
VARA	Estimates variance based on a sample, and includes all text and logical values in
	its calculation
VARP	Calculates variance based on the entire population given as arguments
VARPA	Calculates variance based on the entire population given as arguments, including
	text and logical values
VDB	Returns the depreciation of an asset for any period you specify, including partial
	periods, using the double-declining balance method or some other method you
	specify
VLOOKUP	Searches for a value in the leftmost column of a table, and then returns a value in
	the same row from a column you specify in the table
VLOOKUP	Searches for a value in the leftmost column of a table, and then returns a value in
	the same row from a column you specify in the table. If range_lookup is
	FALSE, an exact match will be found. If range_lookup is TRUE, an
	approximate match will be found.
WEEKDAY	Returns the day of the week corresponding to a given date
WEIBULL	Returns the Weibull distribution
YEAR	Returns the year corresponding to a given date
ZTEST	Returns the two-tailed P-value of a z-test

Some background art spreadsheet applications and spreadsheet components allow users to define functions that are not built-in. KDJUserDefinedFunctionLibrary is a set of functions defined in the target software development language that represent behavior aspects necessary for execution of user-defined spreadsheet functions. In a preferred embodiment, KDJUserDefinedFunctionLibrary is an object-oriented software class. KDJUserDefinedFunctionLibrary allows unanticipated functions to be made available for use in KDJCell formulas. All member functions of KDJUserDefinedFunctionLibrary must be defined as static and require no instantiation. In a preferred embodiment, KDJUserDefinedFunctionLibrary can be generated and only include implementations of the user-defined spreadsheet functions actually used in the specific workbook for which code is generated. This serves to optimize the generated code for size. The entire library of user-defined spreadsheet functions can be used if the Calculation Engine is to be shared by modules representing several workbooks, where the used functions may not be known at code-generation-time.

	Description

Field
<<none>>	In a preferred embodiment,
	KDJUserDefinedFunctionLibrary has no fields.
Method
DollarToWords	A function for converting a currency amount to a word
	representation for use in printing checks. For example,
	(123.45) would return ‘One Hundred Twenty Three
	Dollars and Forty Five Cents’.
. . .	A multitude of unanticipated user-defined functions can
	be defined and made available for use by KDJCell
	formulas.

Claims (23)

1. A computer-readable medium containing instructions for implementing a source code generator for use with a computer system the source code generator comprising:

an interface configured to receive a user-specification of spreadsheets that include spreadsheet data for which source code is to be generated, and a specification of spreadsheet cells for which no source code is to be generated where the cells are specified by setting cell attributes as markers for exclusion;

a data acquisition interface configured to receive the spreadsheet data;

a parser configured to extract information from the spreadsheet data received by the data acquisition interface excluding the spreadsheet cells for which the specification was received by the interface; and

an information processor configured to perform a data transformation of the information extracted by the parser into source code representative of the spreadsheet data.

2. A source code generator as recited in claim 1, wherein the source code conforms to a grammar and syntax of a software language.

3. A source code generator as recited in claim 1, comprising data structures representative of entities associated with spreadsheet data.

4. A source code generator as recited in claim 3, wherein said parser instantiates software data structures representative of one or more of spreadsheet sheets, cells, and names.

5. A source code generator as recited in claim 4, where the source code declares and defines object oriented software classes tat implement features of the spreadsheet data where the object oriented software classes can be instantiated at runtime to provide a calculation and data access features of the spreadsheet data.

6. A source code generator as recited in claim 5, wherein the object oriented software class declares an instance of the object oriented software class wherein data member values of the instance are representative of the cell and any source code representative of the cell's formulaic expression.

7. A source code generator as recited in claim 6, wherein the source code generator is configured to generate an object oriented software function as a member of the source code representative of the spreadsheet sheet enclosing the cell.

8. A source code generator as recited in claim 6, wherein the source code representative of a cell's formulaic expression contains direct references to named cells rather than the names.

9. A source code generator as recited in claim 1, further comprising a function descriptor that supports generic generation of code representative of calls to native spreadsheet functions.

10. A source code generator as recited in claim 1, wherein said source code declares and defines member data and functions for accessing run-time-instantiated instances of generated source code representative of said spreadsheet sheets, cells, and names.

11. A source code generator as in claim 10, where said source code comprises a grammar specifying a computer-executable language.

12. A source code generator as recited in claim 1, wherein said parser is a recursive descent software module.

13. A source code generator as recited in claim 1, where the interface is further configured to receive user-specification of a range of spreadsheet cells within each spreadsheet sheet for which source code is to be generated.

14. A source code generator as recited in claim 13, where the interface is further configured to receive spreadsheet cells for which source code is to be generated where the cells are specified by setting cell attributes as markers for inclusion.

15. A source code generator as recited in claim 14, where said marker for inclusion is cell foreground color and cell background color.

16. A source code generator as recited in claim 1, where the marker for exclusion is cell foreground color and cell background color.

17. A source code generator as recited in claim 1, comprising source code implementations representative of built-in spreadsheet functions.

18. A source code generator as recited in claim 1, wherein the source code includes implementations representative of built-in spreadsheet functions only where the built-in spreadsheet functions are referred to in the spreadsheet data.

19. A source code generator as recited in claim 1, comprising source code implementations representative of user-defined spreadsheet functions.

20. A source code generator as recited in claim 1, wherein the source code includes implementations representative of user-defined spreadsheet functions only where the user-defined spreadsheet functions are referred to in the spreadsheet data.

21. A computer-readable medium containing instructions for implementing a source code generator for use with a computer system the source code generator comprising:

a data acquisition interface configured to receive spreadsheet data;

a parser configured to extract information from the spreadsheet data, and

an information processor configured to perform a data transformation of extracted information into source code representative of the spreadsheet data, which excludes implementations of built-in spreadsheet functions that are not referred to in the spreadsheet data.

22. A computer-readable medium containing instructions for implementing a source code generator for use with a computer system the source code generator comprising:

a data acquisition interface configured to receive spreadsheet data;

a parser configured to extract information from the spreadsheet data, and

an information processor configured to perform a data transformation of extracted information into source code representative of the spreadsheet data, which

excludes implementations of user-defined spreadsheet functions that are not referred to in the spreadsheet data.

23. A computer-readable medium containing instructions for implementing a source code generator for use with a computer system the source code generator comprising:

a data acquisition interface configured to receive spreadsheet data;

a parser configured to extract information from the spreadsheet data, and

an information processor configured to perform a data transformation of extracted information into source code representative of the spreadsheet data, including:

identifying and isolating a first spreadsheet cell formula having a similar structure as a second spreadsheet cell formula;

generating parameterized source code representative of the structure;

generating source code representative of the first spreadsheet cell formula that calls the generated parameterized source code; and

generating source code representative of the second spreadsheet cell formula that calls the generated parameterized source code.

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